A systematic review of the association between sedentary behaviors with frailty

Objective: Lifestyle factors such as physical activity are known to reduce the risk of frailty. However, less is known about the frailty-sedentary behavior relationship. A systematic review was conducted to synthesize the available evidence concerning associations between sedentary behaviors and frailty levels in adults. Method: MEDLINE, Embase, Web of Science, CINAHL, SPORTDiscus, Scopus, and the World Health Organization Clinical Trials Registry were searched up to August 2017 for observational studies in adults > 18 years for cohort studies. Included studies identified frailty as a specified outcome using a multi-component tool. Sedentary behavior was measured by self-report or objectively. Studies with statistical models adjusting for at least one covariate were included. Meta-analysis could not be performed due to the heterogeneity in frailty and sedentary behavior measures. Results: Six longitudinal and ten cross-sectional studies were identified (n=14, 693 unique participants); sample sizes ranged from 26 to 5871. Studies were generally at a low to moderate risk of bias. Most studies (n=9) used the Fried criteria to measure frailty. Five studies measured sedentary behavior by questionnaire, with three studies specifically measuring television viewing time. Seven studies measured sedentary time by accelerometry. Thirteen of sixteen studies observed a detrimental association between high amounts of sedentary behaviors and an increased prevalence of frailty or higher frailty levels. Six of seven studies adjusting for physical activity behaviors demonstrated an independent association between sedentary behaviors and frailty. All six longitudinal studies found a negative association between sedentary behaviors and frailty. Conclusions: Sedentary behaviors were associated with a higher prevalence of frailty or higher frailty levels. Longitudinal studies are needed that adjust for physical activity when determining the association between sedentary behaviors and frailty. The efficacy of sedentary behavior reduction outside of physical activity interventions to treat and reverse frailty should also be tested.